Mail & Guardian | 7 July 2008
The biological clock ticks for men as well as women, doctors warn on Monday, after research found that male fertility begins to decline when they reach their mid-30s.
Doctors said men who wait until their 40s before starting a family face a greater chance of their partner having a miscarriage, because of the poorer quality of their sperm.
Researchers examined patient records of more than 12 000 couples treated at a fertility clinic in Paris, and separated out the influence of male and female ages on the couples’ chances of having a baby.
They found that women whose partners were 35 or older had more miscarriages than those who were with younger men, regardless of their own age. The men’s ages also affected pregnancy rates, which were lower in the over-40s.